This invention pertains to cleaning agents and, in particular, to such cleaning agents for use in removing weathering, micro-organisms and dirt from all stone structures and products.
The most common approaches that currently exist in the cleaning of stone monuments, memorials buildings and other stone items are the use of physical cleaning devices, such as sandblasting units, and the use of strong acids, such as muriatic acid and high water pressure devices (minimum of 100 pounds per square inch required). The stone being cleaned can be granite, slate, marble or similar stone. All these approaches have problems associated with their use. Sandblasting equipment and high pressure devices are expensive and, therefor, not economical for small stone cleaning. Additionally, the use of this technique can harm nearby shrubs and grass and the user must exercise caution to avoid those difficulties. The use of straight acidic cleaners can be harmful to the hands and the face of the user and can kill nearby shrubbery and grasses and, at the same time, can discolor the stone being cleaned. What is needed is a cleaning agent that is economical to use. Additionally, what is needed is a cleaning agent that is effective and is not harmful to the user or the environment when used as directed. Clearly, it is desirable for a cleaning agent that does not contain the limitations described above and at the same time is simple and practical to operate. It is the object of this invention to set forth an improved cleaning agent which avoids the disadvantages and limitations, recited above in current cleaning agents. The mixture disclosed in U.S. Pat. No. 4,897,213 is a cleaning agent that meets these requirements. However, what is needed is an improved mixture which works in an improved fashion.